The chemical, which gives some cola-flavoured drinks their caramel colour, has been linked to causing cancer according to laboratory tests.
The levels of the additive, known as 4-methylimidazole (4-MI), have already been reduced in Coca-Cola and Pepsi in the United States, after the state of California stipulated any food or drink containing it must be labelled with a cancer warning.
No such change has yet been adopted in Britain or the rest of the world.
Campaigners have now called on manufacturers to “respect the health of consumers”, and intend to write to health ministers calling for a ban of the colouring,
Coca-Cola strenuously denies there is any human health risk from 4-MI, claiming no food safety watchdog in Britain and Europe has assessed it as a concern. The drink complies fully with European laws.
According to research by American group Center for Science in the Public Interest, the amount of 4-MI found in British cans of Coca-Cola is 135 micrograms – 34 times higher than that found in the US drinks.
Laboratory tests have shown that 4-MI can lead to increased tumours in animals, but no reports have been detected in humans.
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Malcolm Clark, campaign co-ordinator at the Children’s Food Campaign, told the Daily Mail: “Coca-Cola seems to be treating its UK consumers with disdain. The company should respect the health of all of its customers around the world, by using caramel colouring that is free of known cancer-causing chemicals.
“The UK Government must regulate to protect public health from companies that aggressively market sugar-laden drinks that lead to obesity, diabetes and tooth decay.”
In March this year, Coca-Cola and Pepsi announced they would be changing their secret formulas in the United States to reduce the level of the chemical.
The state of California had stipulated any food or drink containing the additive 4-methylimidazole (4-MI) must be clearly labelled with a cancer warning.
The law was passed following a campaign by consumer rights groups.
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A spokesman for the British Soft Drinks Association told the Daily Mail there was no need to ban caramel colours containing 4-MI and said: “The 4-MI levels found in food and drink products pose no health or safety risks.
“Outside the state of California, no regulatory agency in the world considers the exposure of the public to 4-MI as present in caramels as an issue.”
Coca-Cola said it already planned to alter the use of the caramel colouring in Britain, but could not disclose a timescale for the change.
It said: “We intend to expand the use of the reduced 4-MI caramel globally as this will allow us to streamline and simplify our supply chain, manufacturing, and distribution systems.”
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A spokesman has said previously: “Caramel is a perfectly safe ingredient and this has been recognised by all European food safety authorities.“The caramel colour in all of our ingredients has been, is and always will be safe. That is a fact.”